The overall objective of this project is to examine the effect of contraceptive steroids and naturally-occurring gonadal hormones on the regulation of circulating glucagon, prolactin, and parathormone in women. Specific goals for the current year included: 1) To determine which contraceptive steroid is responsible for the blunting of glucagon secretion, and whether contraceptive steroid is responsible for the blunting of glucagon secretion, and whether contraceptive steroid blunting of glucagon secretion accounts for the elevation in serum triglyceride and cholesterol concentrations observed in women using birth control pills; 2) To assess the lactogenic effect of nortestosterone derivatives in women using contraceptive steroids; 3) To develop radioimmunoassays for the 1-34 amino terminal peptide of human parathormone and other parathormone-like peptide fragments isolated from the sera of patients with renal osteodystrophy which could be used in examining the effects of pregnancy and contraceptive steroids on parathyroid physiology.